Thousands of schoolchildren enjoyed an extra day's holiday in the Arctic weather yesterday.

More than 50 schools in the north of England were shut as the big freeze tightened its grip, causing travel chaos.

Weather experts warned the icy weather will continue for three weeks and could mean one of the coldest winters for 100 years.

In areas of Cumbria, deep snow left vehicles stranded, with the council working flat out to grit primary routes.

Parts of Scotland are expected to hit -14C at night over coming days with the rest of the UK averaging -5C.

Yesterday The National Grid warned power suppliers to use less gas as it saw a 30% rise on normal seasonal demand. It is only the second time this has happened.

National Grid said: "Big generators like E.ON can choose to switch to coal."

Meanwhile, many local authorities ran out of road salt and grit. In Kent, DIY stores used up supplies as desperate councils turned to them.

Meanwhile, streams and waterfalls in the Brecon Beacons froze, while blizzards in Teesside left many stranded at home. In London, a thick sheet of ice covered fountains in Trafalgar Square.

In Scotland, with up to 20in of snow predicted in some areas, thousands were marooned at home as roads remained ungritted. Stuart Russell, 45, a council gritter driver in West Lothian, pleaded for patience. He said: "You get a lot of abuse from the public, but we've been starting at 8am and finishing at 11pm, seven days a week. We never got any Christmas."

And Britain was again hit by travel chaos as millions went back to work.

The AA attended more than 22,000 breakdowns yesterday - about two and-a-half times more than a normal Monday. They said a fortnight of freezing temperatures had left thousands of cars stranded with flat batteries and frozen engines, with many accidents on slippery roads.

And commuters in the capital faced misery yesterday morning when festive engineering works remained unfinished at London's Liverpool Street. Elsewhere, buses replaced trains between Ormskirk and Preston and between Boston and Skegness, Lincs, while a signalling problem near Dagenham Dock, Essex, led to delays.

Police were investigating yesterday after the body of a woman aged 59 was discovered beneath ice in a pond in Frampton-on-Severn, Glos. Officers are not treating it as suspicious.

Police and mountain rescue teams, along with an RAF helicopter, were yesterday searching for a man who disappeared in freezing temperatures. Ian Simpkin, 36, of Wath, North Yorks left home on foot on Sunday at 10am.

MeteoGroup said winds are bringing in cold air from the Arctic. Senior meterologist Stephen Davenport said: "Should conditions continue in a similar vein then by March we might just be looking back at one of the coldest winters of the last 100 years."

Joe Bastardi, at Accuweather, warned: "Global cycles mean weather is going to get worse over 20 to 30 years. This winter will be especially cold.

"I predict that this year will remain around 1C to 3C below average temperatures easily until March, even April." Bookmaker Paddy Power cut the odds on this being the coldest January on record from 5/1 to 7/4 yesterday.

By tomorrow the South West, Wales, Manchester and Lincoln will see a mix of sleet and showers, which will move towards the South East and East Anglia.

But the snow did some good. Police in Margate, Kent, arrested a suspected shop raider after tracing his footprints.